March 9, 2009
Storm Chase
Central Oklahoma
Editor: Putnam E. Reiter
Forecast/Setup -
Risk Area: Slight Risk
Initial Target Area: El Reno, Oklahoma
SPC Products:
SWODY1
16:30z -
Risk
Area -
Tornado Prob -
Hail Prob -
Wind Prob -
LSR Plot
-
LSR
NAM 00z Initialization:
Surface Pressure
- Dewpoints -
CAPE
- MLCAPE
- CIN
- 0-3 Km Helicity -
Surface Temperature
-
850mb Dewpoints
- 850mb Wind -
850mb Vertical
Velocity
- 700mb Wind
- 700mb Vertical
Velocity -
700mb Relative Humidity
- 500mb Temperature
- 500mb Wind
-
500mb Vertical
Velocity -
500mb Relative Humidify
- 500mb Vorticity -
250mb Wind
- 250mb Relative
Humidity -
00z Wichita Sounding
SPC Case Review
After last Saturday's event, there appeared to be
potential for severe thunderstorms again today.
Moisture got pushed into Texas, but rapidly returned
into Oklahoma. The presence of the subtropical
jet over Oklahoma made forecasting sky conditions
and resultant temperatures quite difficult.
Most forecasters went with (and I agree) cloudy
skies and temperatures in the mid 70s. There
was the additional threat of showers during the
morning hours as a shortwave trof moved across the
state.
The shortwave trof did setoff a few storms across
northern Oklahoma, but these had no impacts on the
threat area. As the system exited it helped
clear skies across western Oklahoma.
Temperatures quickly rose into the upper 70s, with
dewpoints in the upper 50s. This produced CAPE
values up to 1500J/Kg. CU developed across the
area and SPC issued an MCD around 14:15 CDT. A
tornado watch was issued a short time later.
Storms eventually developed around 17:00 as lift
from another shortwave trof moved into western
Oklahoma.
Storms struggled to stay discrete and even the
discrete storms struggled. A few severe
thunderstorm warnings were issued but no tornado
warnings. The best looking storm of the day
seemed to be after dark in north-central Oklahoma.
Some storms may have briefly become supercellular,
but they didn't hold it for long.
Storms continued moving east and eventually became
non-severe by 10pm.
The Chase -
Team 1 - Rob
Ferguson and Putnam Reiter
Miles Driven - 430 - Gas spent $5.00
Departure Time - 15:00 CDT
Return Time - 21:00 CDT
Track Path
We left Oklahoma City and went west on I-40. We got to
El Reno and got some fuel. We knew a hotel nearby that had WiFi, so we
went and setup shop. I'd guess this is around 4pm. We stayed here
until 6pm when the storms to our southwest seemed to have better organization.
We jumped back on I-40 west and went to Exit 108 (the one to Watonga). We
sat on the southwest side of the Interstate and watch the towering CU/some
storms.
About 7:30pm we had enough and
drove north on HWY 281 as the storm near Geary
seemed the strongest of the bunch. Getting
into Geary, the storm look unimpressive and
glaciated. Having another reason to head home,
we turned around and head back south. Jumping
on I-40, we headed on east to OKC and home.
It was nice that storms developed,
but certainly not what was in my forecast or
thinking. This was a case of very strong shear
but limited instability. The lack of a well
defined lifting mechanism given the prior to items
appears to have kept this event from getting more
interesting.
Lessons
Learned -
- Hum, maybe forecasting??? Well, several
other chasers were out, so we had good company.
Multimedia
-
Oklahoma City RADAR -
WMV Format
Encounters
-
Engaged
Storm: South of Geary
Tornado: No
Funnel: No
Hail (larger than 0.75 inches): No
Wall Cloud: No
Wind (above 57.4 mph): No
